Abstract: Multi-spectral images are detected using a refractive objective lens system. Magnesium oxide (MgO) and calcium fluoride (CaF.sub.2) lenses are used to image scenes in both the visible and infra-red (IR) spectrums. The inventors have discovered that the combination of magnesium oxide, only recently made available in a pure crystal form, and calcium fluoride can be used to fabricate an objective lens for imaging objects in both the visible and infra-red spectrums. Moreover, the combination of magnesium oxide and calcium fluoride results in a super-achromatic condition across visible and infra-red spectrums. This chromatically-corrected spectral range includes wavelengths between 0.4 and 5.9 microns which covers medium-wave IR (MWIR), short-wave IR (SWIR), and the near-IR/visible windows. Combinations of MgO and CaF.sub.2 lenses are used in different compound objective lens designs including doublet, Petzval, inverted telephoto, and telephoto arrangements.

Abstract: A levelness adjusting device includes a positioning a unit mounted on a support surface for an actuator unit which is fixed on a frame, in which said positioning a unit comprises a base screw hole to play a support point, several adjusting screw holes which are located on a same circumference centering the base screw hole and are opened at positions adjusted to an inclination of the shaft for rotating a mirror body and several screws threaded into the screw hole so as to fix the actuator unit on the frame. The screw is penetrated from the actuator unit front portion to the frame via the screw hole which is formed on a periphery edge of the actuator unit. The screw is threaded into the base screw hole and the corresponding screw hole, and the actuator unit is positioned on the frame.

Abstract: An optical scanner for use in laser beam printers and the like which is particularly satisfactory in imaging characteristics. A light beam from a semiconductor laser passes through a collimator lens, an aperture diaphragm and a cylindrical lens. The beam is then deflected by a rotating lens mirror and subjected to the focusing action of an imaging lens so that it is focused to form a beam spot, which scans over a scan surface as the beam is deflected. The imaging lens has aspheric surfaces in the main-scanning cross section and is designed so that the rate of change in its curvature and other relevant parameters satisfy a predetermined equation so as to lie within a predetermined range.

Abstract: An optical film of the present invention is of multi-layered structure which has a high-refractive-index layer composed of titanium oxidic nitride, aluminum oxidic nitride, or silicon oxidic nitride.

Abstract: A reflection mirror has reflection steps formed as portions of respective paraboloids of revolution and disposed between adjacent ones of closed curves formed as lines of intersection of a group consisting of the paraboloids of revolution with different focal distances and a fundamental surface for the reflection surface. The fundamental surface for the reflection surface includes a first curved surface portion and a second curved surface portion connected to the first curved surface portion in the n-th order continuity (N.gtoreq.1). The first curved surface portion is shaped such that when a light beam, which is emitted from a point light source supposed to lie on the principal optical axis of the reflection mirror, is reflected at a reflection point on the first curved surface portion, the light beam reflected thereat is directed substantially parallel to the principal optical axis of the reflection mirror.

Abstract: A polarizer having first and second reflecting surfaces which define an angle of 120.degree. therebetween and a beam splitting surface which lies in a bisectional plane of the first and second reflecting surfaces. The first and second reflecting surfaces and the polarization beam splitting surface are arranged to meet at a line which defines an edge of the polarizer.

Abstract: A polarization insensitive, multilayer planar reflection filter is provided having (I) strong sidelobe suppression, preferably with sidelobe suppression levels in the range of -30 dB to -50 dB, and (ii) minimum width of the filtered bandwidth for the specified sidelobe suppression level. The multilayer planar reflection filter is provided by a multilayer stack by specifying the manner in which the thickness of the individual dielectric layers are to be varied throughout the stack. The resulting universal design formula specifies these layer values for a stack with an arbitrary number of layers, dielectric constant, incident angle, and wavelength. In particular, the layer thickness values of the alternating layer d.sub.1 (j) in refractive index n.sub.0, and d.sub.2 (j) in refractive index n.sub.0 +.DELTA.n, vary with each period j and are determined to provide a specified central wavelength, sidelobe suppression and minimum filtered band width.

Abstract: A polarization-independent optical isolator having a structure in which polarization dispersion is virtually eliminated by selecting the thickness and optical axis orientations of birefringent crystalline plates used in the isolator. The optical isolator of the present invention employs a combination of birefringent crystalline plates wherein the optical axis orientation of at least one birefringent crystalline plate in the optical isolator is different from the optical axis orientation of the remaining birefringent crystalline plates, and the polarization mode dispersion, which is induced when the beam propagates through the birefringent crystalline plate having a different optical axis orientation, is equal to the dispersion rate of the polarization mode dispersion attributable to the remaining birefringent crystalline plates and in a mutually inverse direction.

Abstract: An optical scanning apparatus can record image information in a plurality of resolutions by changing the pitch (scanning interval) of light beams in a direction orthogonal to the scanning direction. In the apparatus, a plurality of light beams emitted from a light-source unit having a plurality of light-emitting portions are guided to a deflector via an optical system, and are deflected and reflected by the deflector. The light beams are then guided to a surface to be scanned via an imaging unit, so that the surface is simutaneously scanned by the plurality of light beams. At that time, an angle .theta. between a first line connecting imaged positions of the plurality of light beams on the surface and a second line obtained by the scanning line of the light beams in the scanning direction on the surface, can be changed by an angle adjusting unit.

Abstract: An exposure apparatus for reproducing a mask pattern onto a photo-sensitive surface of a substrate uses holographic techniques. The apparatus includes support for holding a hologram recording plate at a predetermined position during both a recording operation and a reconstructing operation. A first illuminating optical system introduces a light beam from a coherent light source to a mask and irradiates a subject beam produced from the mask into the recording plate. A second illuminating optical system irradiates the light beam from a coherent light source as a reference beam into the recording plate, a carrier apparatus disposes during the reconstructing operation, a substrate at the position of the mask, in place of the mask. A third illuminating optical system for irradiates a conjugate beam with the reference beam into the recording plate, in which a hologram has been formed by the recording operation, to form an image of the hologram on the photo-sensitive surface of the substrate.

Abstract: A holographic stoplight system that includes a stoplight hologram (21, 21') supported adjacent the inside surface of a rear window (211) of a vehicle, and a light source (29, 31) for providing a converging beam that is vertically converging and predominantly horizontally colimated. The stoplight hologram is illuminated with the vertically converging beam, or with a predominantly collimated beam provided by a collimating lens (27) that collimates the vertically converging beam.

Abstract: A membrane device is provided in which a plurality of ridges (14) and recesses (16) are formed proximate to a substrate (12). Electrodes (18) are formed within the recesses (16). A spacer (20) supports a membrane (22). Application of a potential difference between the membrane (22) and the electrodes (18) allows for deflection of the membrane (22) toward the electrodes (18).

Abstract: An image display system for providing images such that a right eye and a left eye of an observer see different images, respectively. The image display system includes: a camera for taking a picture of said observer and then outputting an image of the observer; a pair of liquid crystal display devices transparent to light; an image generation device for generating a back-light image based on an image output signal provided by the camera; a pair of CRT devices for displaying a back-light image generated by the image generation device to illuminate the pair of liquid crystal display devices from their back sides; a mirror for combining images present on the pair of liquid crystal display devices into one image; and optical elements for giving directivity to back-light emitted by the pair of back-lighting devices so that one of the pair of CRT devices provides back-light illumination for the right eye and the other one of the pair of CRT devices provides back-light illumination for the left eye.

Abstract: Stereoscopic perspectives changing with the position of the observer's eyes create a natural depth-impression. An electronically controlled adaptive monitor is disclosed that imitates this feature without any additional devices such as glasses, so that items in front and behind the screen appear in a three-dimensional manner. Alternatively, the monitor can also be used as a high-resolution two-dimensional screen. This combined performance feature is achieved at a reasonable price by mounting a grid-shield with vertical cylinder lenses in front of the monitor. At the focal point of the cylinder lenses is an electronically controlled shadow-line grid-LCD, allowing the alternating passage of right and left pictures sequentially at 100 or 120 Hz. Depending on the position of the observer, the location of the shadow-lines is changed adaptively, while the respective right- and left-eye perspectives of the 3D-picture can be calculated in real-time simultaneously.

Abstract: Apparatus performs polarization dependent functions although the apparatus is polarization independent with respect to the outside world. The apparatus produces parallel beams with like polarization, and the parallel beams are then subject to polarization dependent processing.

Abstract: An optical scanner having a light source for emitting a light beam, an optical deflector having a deflecting-reflecting face for deflecting the light beam at a constant angular speed and a scan image forming mirror for reflecting the deflected light beam to a surface to be scanned at a constant speed. The light source and the optical deflector are provided on opposite sides across the scan image forming mirror and the light beam is illuminated toward the deflecting-reflecting face of the optical deflector through an emitted-light transmitting portion provided outside an effective area of the scan image forming mirror.

Abstract: A holographic apparatus for continually sensing, transmitting and reconstructing a three-dimensional image including a device for receiving a holographic interference pattern such as a video camera, a device for creating a holographic interference pattern on the receiving device, a device for focusing the interference pattern on the input of the receiving device, a device for transmitting the received holographic interference pattern including a device such as a computer, a device for converting the transmitted holographic interference pattern to a holographic interference pattern which is representative of the three-dimensional image such as an LCD and a source of coherent light illuminating the holographic interference pattern on the converting means to reconstruct the three-dimensional image.

Abstract: A head-mounted image display apparatus (HMD) including an ocular optical system, which has an F-number of 1.5 to 3 and enables a flat and clear image to be observed at a view angle of up to 60.degree. or more with substantially no aberration. The HMD has at least two, surfaces and each having a concave surface directed toward the pupil. The two surfaces are disposed so that light rays from an image display device are reflected by the first surface, and the reflected light rays are reflected by the second surface and pass through the first surface to enter an observer's eyeball.

Abstract: A three-dimensional photo mask is formed from a substrate having a first side and a three-dimensional side. A hologram is provided on the first side of the substrate. The three-dimensional side of the substrate has a photosensitive resist material provided thereon. The hologram includes information that defines features to be imaged onto the photosensitive resist material. A method and a system are disclosed for producing the three-dimensional mask.

Abstract: An display apparatus has an image displaying device for modulating light by a spatial light modulation element and displaying an image, a relay optical system for forming the image on an imaging plane at a location differing from the image displaying device, an eyepiece optical system for directing the light from the imaging plane to an observer's pupil, and light beam controlling device provided in a portion of the relay optical system for controlling the amount of transmission of a light beam from the image displaying device correspondingly to the inclination of the contrast distribution of the light beam.